The present invention is directed to an improved method and apparatus for calibrating and adjusting the quantity, rate, and density of granular material applied to an agricultural field by an agricultural planting device. More particualarly, the present invention provides means for readily and efficiently calibrating the rate and density of a granular chemical pesticide or insecticide applied to a field from an agricultural planter device during a planting procedure.
By way of background, and agricultural planter is a wheeled device or implement which is adapted to be towed by an agricultural vehicle such as a tractor. Agricultural planters, which are well known to those skilled in the art, physically place seed in a field as the tractor is driven over rows to be planted. The planter includes a planting mechanism which is mechanically coupled by a gear train or transmission to the axle of the planter vehicle so that the motion of the planter vehicle drives the planter mechanism when planting of seed is desired. The planter mechanism may be moved into a neutral position in which the gear train is disengaged so that the planter vehicle may be towed but seed will not be planted. The planter mechanism will be set in its neutral position when, for example, the tractor which tows the planter is driven over areas which are not to be seeded. Further information concering the operation of planter devices towed by agricultural vehicles may be obtained by reference to The 1988 Long Green Line Catalog and Drawn, Integral And Unit Planters, both of which are published by John Deere & Co., the disclosures of which are expressly incorporated by reference herein.
Planter devices of the type discussed above generally inclucde attached bins or containers for holding and applying granular material such as fertilizer, insecticide or herbicide which are typically applied to a field by the planter in conjunction with a planting operation. The bins containing the granular materials are coupled to the planter vehicle axle by mechanical means, such as a gear train or transmission which is selectively coupled to the rotation of the axle of the planter vehicle, to dispense the granular material as desired during the seeding procedure. The individual bins containing fertilizer, insecticide, herbicide or other granular material may be independently coupled to the axle of the planter vehicle so that the different granular materials in the different bins are applied to the field at different rates and densities. This may be accomplished, for example, by providing step-up or step-down gears in the specific gear trains coupled to the individual bins holding the different granular materials. Accordingly, the rate at which the individual materials are dispensed from the different bins may differ from one another, and may also differ from the rate at which seed is planted, even though the seed planting and granular material dispensing operations are all driven by the motion of the same planter vehicle. Further information concerning the dispensing of granular fertilizer, insecticide or herbicide from bins mounted to an agricultural planter device may be obtained by reference to The 1988 Long Green Line Catalog and Drawn, Integral And Unit Planters, both of which are expressly incorporated by reference herein.
The individual bins containing the granular material to be applied during the planting opertion include both a storage area and an application area. The granular material is moved or transferred in predetermined quantities from the storage area to the application area, as for example by a conventional rotating paddle structure or vacuum transport system driven by the movement of the planter vehicle when the gear train coupling the storage bin to the motion of the planter vehicle is in opeartive engagement. The application area of the bin includes one or more openings of predetermined dimension defined in its bottom surface. Granular material delivered from the bin storage area to the application area is dropped by gravity feed through the bottom copening in the bin and onto the field being seeded. The size of the bottom opening in the bin may be adjusted by conventional means. Accordingly, the speed at which the vehicle is driven, and the selected size of the opening in a bin containing granular material, determine the rate at which the granular material is applied to the agricultural field over which the vehicle is driven.
The density of application of the granular material, (i.e., the quantity of material applied per linear distance planted), is of significant importance to the planting operation. When granular pesticide is to be applied during a seeding operation, it is necessary for a farmer to check or adjust the density fo pesticide to be applied before it actually is applied to the field. This is commonly done by mounting collector tubes or containers beneath the bottom apertures in the bins holding the granular material, coupling the planter with the bins to a tractor, and driving the tractor a predetermined distance in the field at the speed which the tractor will be driven during the actual planting operation. The quantity of granular material dispensed from the bin and collected in the collector tube is measured, and this quantity is divided by the linear distance traveled by the tractor to calculate the density at which the granular material would have been applied to the field. If the density is not the desired value, the size of the opening in the bin is adjusted (increased if a greater density of application is required, or decreased if lesser density of application is required), and the same procedure is repeated. This laborious and time-consuming procedure may be repeated a number of times until the bin is calibrated to attain the desired rate of application and density of the granular material.
It is the object of the present invention to provide a method and apparatus for facilitating the procedure by which bins containing granular material, particularly granular pesticide to be applied during a planting operation, may be easily calibrated and adjusted to readily attain the desired density and rate of application to the field to be seeded.